Role Of Candida Research Articles

Interplay between Candida albicans and Lactic Acid Bacteria in the Gastrointestinal Tract: Impact on Colonization Resistance, Microbial Carriage, Opportunistic Infection, and Host Immunity.

Emerging studies have highlighted the disproportionate role of Candida albicans in influencing both early community assembly of the bacterial microbiome and dysbiosis during allergic diseases and intestinal inflammation. Nonpathogenic colonization of the human gastrointestinal (GI) tract by C. albicans is common, and the role of this single fungal species in modulating bacterial community reassembly after broad-spectrum antibiotics can be readily recapitulated in mouse studies. One of the most notable features of C. albicans-associated dysbiotic states is a marked change in the levels of lactic acid bacteria (LAB). C. albicans and LAB share metabolic niches throughout the GI tract, and in vitro studies have identified various interactions between these microbes. The two predominant LAB affected are Lactobacillus species and Enterococcus species. Lactobacilli can antagonize enterococci and C. albicans, while Enterococcus faecalis and C. albicans have been reported to exhibit a mutualistic relationship. E. faecalis and C. albicans are also causative agents of a variety of life-threatening infections, are frequently isolated together from mixed-species infections, and share certain similarities in clinical presentation-most notably their emergence as opportunistic pathogens following disruption of the microbiota. In this review, we discuss and model the mechanisms used by Lactobacillus species, E. faecalis, and C. albicans to modulate each other's growth and virulence in the GI tract. With multidrug-resistant E. faecalis and C. albicans strains becoming increasingly common in hospital settings, examining the interplay between these three microbes may provide novel insights for enhancing the efficacy of existing antimicrobial therapies.

Candida species in community-acquired pneumonia in patients with chronic aspiration

BackgroundWhen Candida species is found in a sputum culture, clinicians generally dismiss it as a contaminant. We sought to identify cases of community-acquired pneumonia (CAP) in which Candida might play a contributory etiologic role.MethodsIn a convenience sample of patients hospitalized for CAP, we screened for “high-quality sputum” by Gram stain (> 20 WBC/epithelial cell) and performed quantitative sputum cultures. Criteria for a potential etiologic role for Candida included the observation of large numbers of yeast forms on Gram stain, intracellular organisms and > 106 CFU/ml Candida in sputum. We gathered clinical information on cases that met these criteria for possible Candida infection.ResultsSputum from 6 of 154 consecutive CAP patients had large numbers of extra- and intracellular yeast forms on Gram stain, with > 106 CFU/ml Candida albicans, glabrata, or tropicalis on quantitative culture. In all 6 patients, the clinical diagnoses at admission included chronic aspiration. Greater than 105 CFU/ml of a recognized bacterial pathogen (Streptococcus pneumoniae, Staphylococcus aureus, or Pseudomonas) or > 106 CFU/ml of other ‘normal respiratory flora’ (Lactobacillus species) were present together with Candida spp. in every case. Blood cultures yielded Candida in 2 cases, and 1,3-beta-D glucan was > 500 ng/mL in 3 of 3 cases in which it was assayed. Since all patients were treated with anti-bacterial and anti-fungal drugs, no inference about etiology can be derived from therapeutic response.ConclusionsCandida spp. together with a recognized bacterial pathogen or normal respiratory flora may contribute to the cause of CAP in patients who chronically aspirate.

Is There Any Relation Between Type 1 Halitosis and Oral Candida Colonisation?

Pathologic halitosis has been classified into 5 types: oral, airway, gastroesophageal, blood-borne and subjective, respectively. Type 1 (oral) halitosis mostly takes origin from anaerobic bacterial activities on oral surfaces. The role of anaerobic bacterial activities is clearly demonstrated, but despite the large number of anectodal claims, the role of Candida in patients with halitosis has not been adequately investigated. The aim of this study was to confirm the relationship between Candida and halitosis. A total of 136 subjects were enrolled and divided into two groups. The study group comprised of 69 patients with halitosis who had over 0.7 ppm H2S concentration in their oral cavity and the control group comprised of 67 healthly subjects. Self assesment scores for halitosis, Candida colony counts in saliva samples, oral NH3, SO2, H2S, H2 and volatile organic gas concentrations were recorded. H2S producing capacity of subjects was quantified by applying cysteine challenge test. Candida samples were taken from the mouths of the patients with and without halitosis, and Candida albicans isolates were inoculated into broth medium. After 3 days of incubation at 37oC, gas concentrations of the headspace of the flasks were read by a portable multigas detector. The rate of Candida positivity was 44.9% in the study group while it was 46.3% in the control group. There was no statistical significant difference between the groups according to the Candida growth (p= 0.561). The oral gas concentrations were comparable in both groups (p< 0.05). Oral H2S concentration increased 9.65 fold with 20 mM cysteine rinse in patients with halitosis while it was increased 5.8 fold in controls. Self assesment for halitosis were well correlated with clinical signs (p= 0.001, r= 0.8). Concentrations of hidrogen and organic gases were found to be increased in all Candida culture media. In this study, no relationship between the presence of Candida and oral halitosis was detected. As a result, there is no need for diets similar to Candida diet in the treatment of halitosis. On the other hand, cysteine challenge can be a useful diagnostic tool. In addition, portable gas detectors can be used as a convenient and practical halitometer to quantify halitosis.

Role of Candida in Catheter Associated Urinary Tract Infection

Role of Candida in Catheter Associated Urinary Tract Infection

Association of Candida species with Oral Submucous Fibrosis and Oral Leukoplakia: A Case Control study

Introduction: Oral Submucous fibrosis (OSMF) and Oral Leukoplakia (OL) are the most common Potentially Malignant Disorders (OPMD’s) seen in South Asia and South East Asian countries. A significant percentage of oral squamous carcinomas develop from pre-existing OPMD’s- Candida organisms is thought to be associated with these lesions. Aim: To determine the incidence and association of candida species in OSMF and OL. Methods: A Case control study was undertaken in 150 participants, which were equally divided into three groups. The smear or swab taken were subjected for Gram staining and Sabouraud’s dextrose agar. The Positive cultured Candida samples were analyzed by using HiMedia M 1297 HiCrome Candida Agar plates for determining the different species of Candida. Chi-square, one-way ANOVA and Tukey HSD Post Hoc test were used as statistical test. Results: The Gram staining was positive in oral swabs of 14 (28%) participants in OSMF group and 20 (40%) participants in OL group. Similarly, the oral swabs in 28% and 40% of the participants from OSMF and OL group were positive, when cultured in Sabouraud’s Dextrose Agar medium. The positive specimens on culturing in HiMedia M 1297 HiCrome Candida Agar plates detected Candida albicans and non albicans significantly (p<0.001) n OSMF and OL group. Conclusions: The Candida albicans and non albicans are associated with OSMF and OL. The findings of our study may act as diagnostic and prognostic marker, although role of candida in carcinogenesis is still a hypothesis and requires more research.

CgMED3 Changes Membrane Sterol Composition To Help Candida glabrata Tolerate Low-pH Stress.

Candida glabrata is a promising microorganism for organic acid production. The present study aimed to investigate the role of C. glabrata Mediator complex subunit 3 (CgMed3p) in protecting C. glabrata under low-pH conditions. To this end, genes CgMED3A and CgMED3B were deleted, resulting in the double-deletion Cgmed3ABΔ strain. The final biomass and cell viability levels of Cgmed3ABΔ decreased by 64.5% and 35.8%, respectively, compared to the wild-type strain results at pH 2.0. In addition, lack of CgMed3ABp resulted in selective repression of a subset of genes in the lipid biosynthesis and metabolism pathways. Furthermore, C18:1, lanosterol, zymosterol, fecosterol, and ergosterol were 13.2%, 80.4%, 40.4%, 78.1%, and 70.4% less abundant, respectively, in the Cgmed3ABΔ strain. In contrast, the concentration of squalene increased by about 44.6-fold. As a result, membrane integrity, rigidity, and H+-ATPase activity in the Cgmed3ABΔ strain were reduced by 62.7%, 13.0%, and 50.3%, respectively. In contrast, overexpression of CgMED3AB increased the levels of C18:0, C18:1, and ergosterol by 113.2%, 5.9%, and 26.4%, respectively. Moreover, compared to the wild-type results, dry cell weight and pyruvate production increased, irrespective of pH buffering. These results suggest that CgMED3AB regulates membrane composition, which in turn enables cells to tolerate low-pH stress. We propose that regulation of CgMed3ABp may provide a novel strategy for enhancing low-pH tolerance and increasing organic acid production by C. glabrataIMPORTANCE The objective of this study was to investigate the role of Candida glabrata Mediator complex subunit 3 (CgMed3ABp) and its regulation of gene expression at low pH in C. glabrata We found that CgMed3ABp was critical for cellular survival and pyruvate production during low-pH stress. Measures of the levels of plasma membrane fatty acids and sterol composition indicated that CgMed3ABp could play an important role in regulating homeostasis in C. glabrata We propose that controlling membrane lipid composition may enhance the robustness of C. glabrata for the production of organic acids.

Antibiotic management of lung infections in cystic fibrosis. II. Nontuberculous mycobacteria, anaerobic bacteria, and fungi.

Airway infections are a key component of cystic fibrosis (CF) lung disease. Whereas the approach to common pathogens such as Pseudomonas aeruginosa is guided by a significant body of evidence, other infections often pose a considerable challenge to treating physicians. In Part I of this series on the antibiotic management of difficult lung infections, we discussed bacterial organisms including methicillin-resistant Staphylococcus aureus, gram-negative bacterial infections, and treatment of multiple bacterial pathogens. Here, we summarize the approach to infections with nontuberculous mycobacteria, anaerobic bacteria, and fungi. Nontuberculous mycobacteria can significantly impact the course of lung disease in patients with CF, but differentiation between colonization and infection is difficult clinically as coinfection with other micro-organisms is common. Treatment consists of different classes of antibiotics, varies in intensity, and is best guided by a team of specialized clinicians and microbiologists. The ability of anaerobic bacteria to contribute to CF lung disease is less clear, even though clinical relevance has been reported in individual patients. Anaerobes detected in CF sputum are often resistant to multiple drugs, and treatment has not yet been shown to positively affect patient outcome. Fungi have gained significant interest as potential CF pathogens. Although the role of Candida is largely unclear, there is mounting evidence that Scedosporium species and Aspergillus fumigatus, beyond the classical presentation of allergic bronchopulmonary aspergillosis, can be relevant in patients with CF and treatment should be considered. At present, however there remains limited information on how best to select patients who could benefit from antifungal therapy.

β-Glucan Antigenemia Anticipates Diagnosis of Blood Culture–Negative Intraabdominal Candidiasis

Life-threatening intraabdominal candidiasis (IAC) occurs in 30 to 40% of high-risk surgical intensive care unit (ICU) patients. Although early IAC diagnosis is crucial, blood cultures are negative, and the role of Candida score/colonization indexes is not established. The aim of this prospective Fungal Infection Network of Switzerland (FUNGINOS) cohort study was to assess accuracy of 1,3-β-d-glucan (BG) antigenemia for diagnosis of IAC. Four hundred thirty-four consecutive adults with abdominal surgery or acute pancreatitis and ICU stay 72 hours or longer were screened: 89 (20.5%) at high risk for IAC were studied (68 recurrent gastrointestinal tract perforation, 21 acute necrotizing pancreatitis). Diagnostic accuracy of serum BG (Fungitell), Candida score, and colonization indexes was compared. Fifty-eight of 89 (65%) patients were colonized by Candida; 29 of 89 (33%) presented IAC (27 of 29 with negative blood cultures). Nine hundred twenty-one sera were analyzed (9/patient): median BG was 253 pg/ml (46-9,557) in IAC versus 99 pg/ml (8-440) in colonization (P < 0.01). Sensitivity and specificity of two consecutive BG measurements greater than or equal to 80 pg/ml were 65 and 78%, respectively. In recurrent gastrointestinal tract perforation it was 75 and 77% versus 90 and 38% (Candida score ≥ 3), 79 and 34% (colonization index ≥ 0.5), and 54 and 63% (corrected colonization index ≥ 0.4), respectively. BG positivity anticipated IAC diagnosis (5 d) and antifungal therapy (6 d). Severe sepsis/septic shock and death occurred in 10 of 11 (91%) and 4 of 11 (36%) patients with BG 400 pg/ml or more versus 5 of 18 (28%, P = 0.002) and 1 of 18 (6%, P = 0.05) with BG measurement less than 400 pg/ml. β-Glucan decreased in IAC responding to therapy and increased in nonresponse. BG antigenemia is superior to Candida score and colonization indexes and anticipates diagnosis of blood culture-negative IAC. This proof-of-concept observation in strictly selected high-risk surgical ICU patients deserves investigation of BG-driven preemptive therapy.

Candida and severe acute pancreatitis: We won't be fooled again

Several studies have suggested a role of candida in infected cases of severe acute pancreatitis. This commentary reports high incidence and mortality rates of candida infection in this setting and demonstrates the value of the colonization index to detect patients at risk for fungal infection. These findings indicate the need to review the place of antifungal therapy and prophylaxis.

IDENTIFICATION OF CANDIDA SPECIES ISOLATED FROM ORAL COLONIZATION IN IRANIAN HIV-POSITIVE PATIENTS, BY PCR-RFLP METHOD

: Background: The incidence of opportunistic infections due to Candida albicans and other Candida spp. has been increasing. Rapid identification of candidiasis is important for the clinical management of immunocompromised patients. Polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP) is a rapid, sensitive, and specific method for detection of clinically important fungi.Objectives: The purpose of this study was to identify Candida spp. isolated from the oral cavities of HIV-infected patients in southeastern Iran (Kerman), by using PCR-based restriction enzyme digestion.Patients and Methods: We identified 96 Candida isolates obtained from 139 Iranian patients infected with the human immunodeficiency virus (HIV), between April 2009 and April 2010, by using PCR-RFLP assay. Universal primers for the internal transcribed spacer (ITS) region (ITS1–ITS4) of the fungal rRNA genes were used for this assay.Results: We successfully identified the different Candida spp. by using the restriction enzyme MspI. C. albicans was the most commonly identified species (82.2%), followed by C. glabrata (7.29%), C. parapsilosis and C. kefyr (both 4.1%), and C. tropicalis (2%).Conclusions: PCR-RFLP is a highly sensitive, specific, and direct method for fungal detection and can be used for fungal epidemiological studies in HIV-positive and other immunocompromised patients. Implication for health policy/practice/research/medical education:To have knowledge about the HIV positive patients and the role of Candida spp. and candidiasis in that group was so important forthe authors. Please cite this paper as:Ayatollahi Mousavi SA, Salari S, Rezaie S, Shahabi Nejad N, Hadizadeh S, Kamyabi H. et al. Identification of Candida Species Isolated From Oral Colonization in Iranian HIV-Positive Patients, by PCR-RFLP Method. Jundishapur J Microbiol. 2012;5(1):336-40. DOI:10.5812/kowsar.20083645.2429 © 2012, AJUMS. Published by Kowsar M.P.Co. All rights reserved.

Candida in oral pre-cancer and oral cancer

Oral pre-malignancies and carcinomas are common epithelial pathologies caused by a variety of etiological factors. In the oral cavity, candidiasis is the most frequent opportunistic fungal infection. Since the initial reports of an association between candidiasis with oral pre-cancer and cancer, various theories have been debated regarding the role of candida in development and transformation of oral pre-malignancies. However, the exact role is still unclear. In the present article, we hypothesize a causal role for candidiasis in oral pre-cancer and cancer albeit an indirect one. We also suggest that candida along with other co-factors may play a role in initiation and promotion of carcinogenesis.

Emerging role of Candida in deep sternal wound infection

Emerging role of Candida in deep sternal wound infection

No Impact of Dectin-1 Polymorphism Y238X On the Outcome of Hematopoietic Stem Cell Transplantation, but a Role for Candida in Acute Graft-Versus-Host Disease.

Abstract 4498Dectin-1 is a C-type lectin receptor that recognizes b-1,3-glucan, and plays an important role in antifungal immunity. The recently discovered dectin-1 Y238X polymorphism, which results in “loss-of-function” has been shown associated with increased Candida colonization of stem cell transplantation (SCT) recipients. Besides its role in antifungal immunity Dectin-1 exhibits a broader function in immunity. Stimulation of Dectin-1 with β-glucan affects antigen presentation, modulates T-lymphocytic (CD4+, both Th1 and Th17, and CD8+) and B-lymphocytic responses, and induces cytokine production including interleukin (IL) 10, IL-12 and IL-23. These specific T-cell responses and cytokines are of particular interest in SCT because they are involved in graft-versus-leukemia (GvL) effects as well as in the pathogenesis of graft-versus-host disease (GvHD). Therefore we now performed a retrospective study in 140 patients on the impact of the Y238X polymorphism on the outcome of myeloablative T cell-depleted matched related SCT. The allele frequency of the Y238X polymorphism was 6.6%, with 10.7% of patients and 15.7% of donors bearing the polymorphism. All were heterozygous and at least one polymorphism was present in 28 of 140 (20%) patient-donor pairs. We found no impact of the polymorphism on the occurrence of acute and chronic GvHD, non-relapse and relapse related mortality, nor disease-free and overall survival. Interestingly, patients from patient-donor pairs bearing the wild-type allele who were colonized with Candida had an increased incidence of acute GvHD compared to non-colonized patients (41.9% vs. 20.4%, OR=2.6 95%CI:1.02-6.58, P=0.04). However, this seemed to be the other way round for patients from pairs with the Y238X polymorphism (23.5% colonized vs. 30% not colonized, OR=0.7, ns). Therefore we hypothesize that the loss-of-function of dectin-1 increases colonization through deficient mucosal immunity, but prevents inflammatory complications resulting from colonization (Figure 1). This might explain the lack of an effect of the Dectin-1 Y238X polymorphism on outcome measures of SCT. [Display omitted] In case of Candida colonization (left) activation of the dectin-1 receptor influences immune responses and allo-reactivity increasing the incidence of acute GvHD. In the presence of the loss-of-function polymorphism Y238X (right), although Candida colonization is increased, due to the loss-of-function of dectin-1, no changes in the allo-reactive T-cell responses occur. Disclosures:No relevant conflicts of interest to declare.

Clinical Aspects of Invasive Candidiasis

Candida endocarditis was previously considered a rare disease. However, its incidence is increasing, partly as a consequence of increased use of prosthetic intravascular devices. In patients with prosthetic valve endocarditis, Candida infection may occur via a two-step process; firstly, post-operative transitory candidaemia occurs during the intensive care unit stay, leading to colonization of the prosthetic valve and subsequent biofilm formation, with reduced susceptibility to antifungal agents. This theory lends support for pre-emptive antifungal therapy with agents that display activity against biofilm-associated Candida in patients with prosthetic heart valves at risk of candidaemia. Current guidelines recommend treatment with amphotericin B with or without 5-fluorocytosine, or an echinocandin, with valve replacement where possible. Recent data suggest that amphotericin B shows reduced activity against Candida biofilm, and poor penetration into vegetations and blood clots in experimental models of infectious endocarditis, whereas echinocandins, and in particular anidulafungin, display potent in vitro activity against sessile Candida cells within biofilms. The incidence of ocular candidiasis has been decreasing among inpatients with candidaemia, possibly because of earlier identification and treatment of candidaemia. The therapeutic approach includes prolonged treatment with fluconazole or voriconazole. The role of systemic echinocandins may be limited since they achieve undetectable vitreous concentrations. Vitrectomy with local instillation of amphotericin B, azoles or echinocandins may play a role in the treatment of chronic complications such as epiretinal membrane formation. The role of Candida in CNS infections is unclear. Diffuse encephalitis in candidaemia is misleading, since alterations of the mental status are generally attributed to candidaemia-associated sepsis syndrome, and neuroimaging studies and cerebrospinal fluid cultures are rarely performed as part of the diagnostic work-up. Osteomyelitis caused by Candida is considered infrequent. In contrast, Candida is frequently implicated in nosocomial non-postneurosurgery spondylodiscitis. Optimal management of such cases may require surgical debridement and, after initial intravenous antifungal therapy, prolonged administration of oral azoles. The role of Candida in endocarditis is fairly well established. With the increasing numbers of patients at risk of Candida endocarditis, there is a need for agents with potent efficacy against Candida biofilms. Echinocandins represent a potential therapeutic option in this setting. Antifungal agents may also be of use in the treatment of complications in patients with ocular candidiasis and in CNS infections.

Onychomycosis and diabetes

This study aims to discuss factors specific to diabetics in the diagnosis and treatment of onychomycosis. Onychomycosis has the potential to cause severe complications in diabetics and should be treated promptly. The existence of comorbid conditions and potential for drug-drug interactions complicates the selection of an appropriate treatment regimen. The role of Candida in onychomycosis is controversial but may be of increased significance in the diabetic population due to an underlying vulnerability to this organism. Terbinafine is an excellent choice in diabetics due to its low risk of drug-drug interaction and proven efficacy against the typical pathogens that cause onychomycosis. Itraconazole, while an effective treatment for onychomycosis, is not a first-choice therapy due to its black-box cardiac warning and numerous drug interactions. Larger studies are needed in diabetics to determine the frequency of candidal nail infections.

Prevalence and role of Candida in acute gastroenteritis (Choleraic and non-choleraic).

ummary Candida species were isolated and identified from the stool samples of cholera and non-dioleraic acute gastroenteritis (GE) cases. From 500 samples (398 from GE and 102 from cholera cases) 129 strains of Candida were isolated. The total rate percentage of Candida in both the groups varied from 25–26 %. The incidence of Candida in GE was higher in children from 1–4 years whereas in cholera cases the incidence was higher in the group from 5–9 years. On statistical analysis it was found that the association of C. albicans and C. tropicalis with gastroenteritis, either choleraic or non-choleraic, bears no significance to the disorder. Complete dissociation of the species of C. albicans and C. tropicalis was found in the stool samples of the two groups of gastroenteritis cases. Zusammenfassung Candida-Arten — 129 Stamme — wurden aus Stuhlproben von Patienten, die an Cholera (102 Falle) oder an einer akuten Gastroenteritis (398 Falle) erkrankt waren, isoliert und identifiziert. Bei beiden Patientengruppen lag der Prozentsatz des Candida-Nachweises zwischen 25 bis 26 %. Das Sprospilzvorkommen lag bei 1–4 Jahre alten Kindern nit einer Gastroenteritis hoher. Bei der Vergleichsgruppe der Cholera-Kranken waren vermehrt Sprospilze bei 5–9 Jahre alten Kindern nachzuweisen. Statistische Berechnungen zeigten keine Verbindung zwischen Candida albicans- und Candida tropicalis-Nachweis zu den Cholera- oder nicht Cholera-bedingten Gastro-enteritiden. Die beiden Candida-Arten wurden in keinem Fall gemeinsam aus einer der Stuhlproben gezuchtet.

Yeast metabolic products, yeast antigens and yeasts as possible triggers for irritable bowel syndrome

Many patients with irritable bowel syndrome (IBS) are disillusioned by the lack of efficacy of treatments and suffer from numerous symptoms not covered by the Rome criteria for IBS, as the current empirical treatment regimens fail to address these persistent debilitating 'IBS associated symptoms'. These symptoms are similar to other symptom complexes like chronic fatigue and the so-called 'candida syndrome', and many seek help from alternative medicine. The possible role of Candida and yeasts in non-immune compromised individuals is disputed and is the subject of this review. Even if the involvement of yeasts in the aetiology of IBS still remains unclear, there is increasing evidence for yeasts being able to cause IBS-symptoms in sensitized patients via Candida products, antigens and cross-antigens. But more research is needed before antifungal treatment can be recommended as a first line treatment for IBS.

Anti-retroviral therapy with protease inhibitors decreases virulence enzyme expression in vivo by Candida albicans without selection of avirulent fungus strains or decreasing their anti-mycotic susceptibility

Highly active anti-retroviral therapies (HAART) with human immunodeficiency virus (HIV) protease inhibitors (PIs) or nonnucleoside reverse-transcriptase inhibitors (NNRTI) were compared for their effect on prevalence, aspartyl proteinase (Sap) production and the biotypes and anti-mycotic sequential susceptibility of Candida spp. isolates from the oral cavity in a longitudinal prospective study. HAART-PI, but not HAART-NNRTI strongly inhibited Sap expression in the oral cavity without exerting any consistent effect on the role of Candida spp. isolation or selection of low virulence or anti-mycotic resistant fungus biotype. More importantly, the sequential isolates of Candida albicans from HAART-PI, but not those from suspended HAART-NNRTI, showed an increased Sap production in vitro. While further demonstrating that HIV-PI inhibit Sap expressions, our results do not support the view that the mentioned inhibition could eliminate Candida or its selection of the oral cavity.

Chronic hyperplastic candidosis/candidiasis (candidal leukoplakia).

Chronic hyperplastic candidosis/candidiasis (CHC; syn. candidal leukoplakia) is a variant of oral candidosis that typically presents as a white patch on the commissures of the oral mucosa. The major etiologic agent of the disease is the oral fungal pathogen Candida predominantly belonging to Candida albicans, although other systemic co-factors, such as vitamin deficiency and generalized immune suppression, may play a contributory role. Clinically, the lesions are symptomless and regress after appropriate antifungal therapy and correction of underlying nutritional or other deficiencies. If the lesions are untreated, a minor proportion may demonstrate dysplasia and develop into carcinomas. This review outlines the demographic features, etiopathogenesis, immunological features, histopathology, and the role of Candida in the disease process. In the final part of the review, newer molecular biological aspects of the disease are considered together with the management protocols that are currently available, and directions for future research.

Atopic dermatitis and fungi.

Atopic dermatitis (AD) is a chronic, itching, inflammatory skin disease which is associated with asthma and/or hay fever and a familial occurrence of these conditions. Genetic factors are important in the development of AD, but the exact hereditary pathway is still unknown. Dry skin and the weakened barrier function in patients with AD is very important for the patient's reactions to irritants and other external trigger factors including microorganisms. The standard treatments are topical corticosteroids, topical immunomodulating agents, and emollients. If AD cannot be controlled by this type of treatment, systemic immunomodulating agents may be used. UVB, UVA, or psoralen-UVA may also be used for widespread severe lesions. However, some patients do not respond to these standard treatment, and then it is important to consider the role of microorganisms, house dust mites or food. The role of the Malassezia yeasts in AD, especially AD located to the head and neck region, is now documented in several papers. There are also several papers indicating the role of Candida as an aggravating factor in AD. Patients with AD also develop chronic dermatophyte infections more easily, and patients with AD and chronic dermatophyte infections may show improvement in their AD when treated with antifungal drugs.